Ruby Seedless and Beauty Seedless grapevines were used to investigate the effect of some compounds producing ethylene effects (ethrel, ethanol, and methanol), cluster thinning, shoulders thinning and girdling on berry quality during 2006 and 2007 seasons. The compounds exercising ethylene effects had a pronounced effect on berry chemical properties and advanced the ripening. Thinning by removing the undesirable clusters or shoulders increased berry; cluster weight and improved berry quality. The cluster or shoulders thinning had a significant effect on the 100 berries and cluster weight. Girdling had little effect on berry quality, but increased weight of cluster and 100 berries compared to the control.